The present invention relates to an improvement of an information storage medium capable of recording and/or reproducing memory card, disc (phase changed optical disc, magneto-optical disc, or magnetic disc, etc.) or the like.
In particular, the present invention relates to an improvement of a removable and portable information storage medium suitable for recording and/or reproducing digital image information in combination with digital audio information.
In addition, the present invention relates to a method for reproducing information recorded in the information storage medium.
Further, the present invention relates to a method for editing information recorded in the information storage medium.
As a removable and portable information storage medium for recording digital audio information, there exists:
(A) CD-DA (compact disc having digital audio recorded in a pit shape);
(B) CD-I (CD interactive) or video CD;
(C) DVD (digital versatile disc) video or DVD audio disc (phase changed recording);
(D) MD (disc utilizing magneto-optical recording); and
(E) solid audio (semiconductor memory card such as flash memory) or the like.
With respect to the shape of information storage medium, the above (A) to (D) has a disc shape. In these information storage mediums, convergent laser beam(s) is (are) emitted to a recording layer on a medium while the medium is being rotated, and a change in the reflection light is detected as a reproduction signal.
In contrast, the above (E) may have any size and/or shape, but roughly has a card shape. In the (E), digital audio information is recorded in a semiconductor memory (mainly flash memory) incorporated in the card shaped body so that audio information is recorded and/or reproduced via electrode terminals provided at a predetermined portion of the card surface.
The CD-DA in the above (A) is used exclusively for reproduction or playback. A user cannot add new audio information, and cannot edit audio information already recorded on an information storage medium. Further, this CD-DA has a format which does not support recording of still image information on the information storage medium.
In contrast, each of the CD-I or video CD of the above (B) and the DVD video or DVD audio of the above (C) has a format which enables to reproduce audio information, and at the same time, to display still image. However, since both of them are exclusive for reproduction only, it is impossible not only to add new audio information by a user, but also to edit the audio information already recorded on the information storage medium.
On the other hand, in MD of the above (D), new audio information can be recorded in the information storage medium by the user, and edit processings such as “combining music (Combine)”, “dividing music (Divide)”, and “Moving music (Move)” can also be performed.
However, MD does not have such a format that a still image can be displayed simultaneously during audio information reproduction.
Apart from package media of the above (A) to (C), in recent years, there becomes popular a system in which digital audio information compressed by MP3 (MPEG audio layer 3) or AAC (MPEG audio advanced audio coding) is distributed on the Internet, the compressed audio information is recorded in a memory card (mainly flash memory) of the above (E) on a receiving party, and the recorded memory card is reproduced while the user is carrying it.
In this case, the user can record new audio information in the memory card, and can edit recorded audio information. However, in this case as well, at present, it does not have such a format that a still image according to audio information can be recorded or edited.
As in CD-I, video CD or DVD audio, the market strongly desires introduction to an audio system capable of reproducing audio information, and at the same time, displaying still image information, and further, capable of recording or editing new audio information by a user.
In addition, in this system, edit functions of a grade such as “Combining music” or “Dividing music” are required.
However, after “Combining must” or “Dividing music” has been performed, in the case where audio information is reproduced in units of music, it is very difficult to determine a method for selecting still image information to be displayed simultaneously and a timing of displaying each item of the still image information.
For example, assume a case wherein music number #α and music number #β having the same reproduction time periods have been recorded, 20 still images are displayed during reproduction of music number #α while these images are changed within a short period of time, and only one still image is continuously displayed during reproduction of music number #β.
In the case where music number #α and music number #β are combined by editing to make music number #γ if the first 20 still images are displayed to be changed within a short period of time during reproduction of music number #γ, and only the last one image is continuously displayed for a long period of time, the user feel strange.
In addition, in the case where music number #θ is divided into music number #ι and music number #κ, there is a problem with how to set still images displayed in music number #ι and music number #κ, respectively.
There does not exist, including the aforementioned MD (by which editing after recording is possible), any format (or specification) which explicitly indicates the guidelines for an optimal method of displaying still images (or still pictures) after edit processing such as “Combining music” or “Dividing music” has been performed.